Rankine Cycle

Abstract

The Rankine cycle ( 31 ) includes a refrigerant pump ( 32 ), a heat exchanger ( 36 ), an expander ( 37 ), and a condenser ( 38 ). The Rankine cycle ( 31 ) shares the condenser ( 38 ) and refrigerant with a refrigerant cycle of an air-conditioner. A refrigerant passage connecting to an outlet of the condenser ( 38 ) branches at a refrigeration cycle branch point ( 45 ) to connect to the refrigerant pump ( 32 ) and an evaporator ( 55 ). In the case of operating the Rankine cycle, without a request to operate the air-conditioner, the compressor ( 52 ) in the refrigeration cycle is driven.

1 . A Rankine cycle provided including: a refrigerant pump that circulates a refrigerant; a heat exchanger that causes the refrigerant to recover waste heat of an engine; an expander that converts the waste heat recovered in the refrigerant by expanding the refrigerant; and a condenser that condenses the refrigerant expanded by the expander, the Rankine cycle sharing the condenser and the refrigerant with a refrigeration cycle of an air-conditioner,
 wherein a refrigerant passage connecting to an outlet of the condenser branches at a branch point to connect the refrigerant pump and an evaporator in the refrigeration cycle,   wherein an air-conditioner circuit valve is provided between the branch point and the evaporator, and   wherein the Rankine cycle comprises a controller that, in the case of operating the Rankine cycle, drives a compressor in the refrigeration cycle, and while driving at least the compressor, closes the air-conditioner circuit valve or decreases an opening degree of the air-conditioner circuit valve, without a request to operate the air-conditioner.   
     
     
         2 . The Rankine cycle according to  claim 1 ,
 wherein the controller drives the compressor in the refrigeration cycle without a request to operate the air-conditioner before starting operation of the Rankine cycle.   
     
     
         3 . (canceled) 
     
     
         4 . The Rankine cycle according to  claim 1 ,
 wherein the controller continues the closing of the air-conditioner circuit valve or the decreasing of the opening degree until it is requested to operate the air-conditioner.   
     
     
         5 . The Rankine cycle according to  claim 1 ,
 wherein the evaporator is disposed at a position above the refrigerant pump.   
     
     
         6 . The Rankine cycle according to  claim 1 ,
 wherein a refrigerant passage from the condenser to the evaporator is disposed at a position above the inlet of the refrigerant pump.   
     
     
         7 . The Rankine cycle according to  claim 1 ,
 wherein a refrigerant passage connecting to the inlet of the refrigerant pump extends upward from the inlet of the refrigerant pump, and the inlet of the refrigerant pump is provided with a pump upstream valve that is closed while the Rankine cycle is being stopped.   
     
     
         8 . The Rankine cycle according to  claim 1 ,
 wherein in the case of driving the compressor when it is not requested to operate the air-conditioner, the controller stops a blower fan of the air-conditioner.   
     
     
         9 . The Rankine cycle according to any  claim 1 , the Rankine cycle being mounted on a vehicle,
 wherein the controller sets a driving time of the compressor in accordance with a stop time of the vehicle performed before starting driving of the Rankine cycle.   
     
     
         10 . The Rankine cycle according to  claim 1 ,
 wherein in the case of driving the compressor when it is not requested to operate the air-conditioner, the controller reduces a compressor driving time as a rotational speed of the compressor is higher.   
     
     
         11 . The Rankine cycle according to  claim 1 ,
 wherein in the case of driving the compressor when it is not requested to operate the air-conditioner, when there is a possibility that a compressor inhale refrigerant pressure may become negative, the controller stops the driving of the compressor.   
     
     
         12 . The Rankine cycle according to  claim 8 ,
 wherein while the blower fan is being stopped, when there is a possibility that a refrigerant which is not evaporated by an evaporator in the refrigerant cycle may be inhaled by the compressor, the driving of the compressor is stopped.